I have a 2015 Lexus LS460 and my passenger side view mirror will not adjust horizontally only vertically. Driver side is fine. Auto fold works fine. Also when in reverse the passenger mirror does not tilt down. Any ideas what the issue might be?

 

So the passenger side will tilt up and down when adjusting manually but will not adjust downward when put in reverse ? You could start by moving the selector from the L to the R position to see if that changes anything for the reverse function.